2,437 research outputs found

    An integrated ecological approach to urban green spaces planning in Beijing, China

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    The Flock Hill Workshop was held on 18-19th November 2009 at Lincoln University. The theme was Urban Ecology and Ecological Design: Perspectives in Integration and Future Directions.The main goals of the workshop were to identify ways in which ecology and design can be successfully integrated and to determine future research and teaching directions in urban ecology and ecological design. Now more than ever we need to understand the role of urban ecology and design in dealing with social, climatic, economic and biodiversity crises in a rapidly changing world. This presentation focuses on an integrated ecological approach to urban green spaces planning in Beijing, China.Project duration 2006-2008, funded by the Chinese Academy of Sciences

    Association of tumor necrosis factor genetic polymorphism with chronic atrophic gastritis and gastric adenocarcinoma in Chinese Han population.

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    0.05). However, TNF-beta Ncol*1/2 and d2/d6 genotypes did not relate to age, gender, grade of differentiation and clinicopathologic stage in patients with gastric adenocarcinoma. The frequency of TNFa6b5c1 haplotype homozygote was significantly lower in patients with gastric adenocarcinoma than in healthy controls (1.79% vs 15.85%, P=0.006). CONCLUSION: TNFa10 allele may be a risk factor for chronic atrophic gastritis. TNF-beta Ncol*1/2 and d2/d6 genotypes are associated with the susceptibility to gastric adenocarcinoma, whereas TNFa6b5c1 haplotype homozygote may contribute to the resistance against gastric adenocarcinoma

    Resonances in J/ψ→ϕπ+π−J/\psi \to \phi \pi ^+\pi ^- and ϕK+K−\phi K^+K^-

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    A partial wave analysis is presented of J/ψ→ϕπ+π−J/\psi \to \phi \pi ^+\pi ^- and ϕK+K−\phi K^+K^- from a sample of 58M J/ψJ/\psi events in the BES II detector. The f0(980)f_0(980) is observed clearly in both sets of data, and parameters of the Flatt\' e formula are determined accurately: M=965±8M = 965 \pm 8 (stat) ±6\pm 6 (syst) MeV/c2^2, g1=165±10±15g_1 = 165 \pm 10 \pm 15 MeV/c2^2, g2/g1=4.21±0.25±0.21g_2/g_1 = 4.21 \pm 0.25 \pm 0.21. The ϕππ\phi \pi \pi data also exhibit a strong ππ\pi \pi peak centred at M=1335M = 1335 MeV/c2^2. It may be fitted with f2(1270)f_2(1270) and a dominant 0+0^+ signal made from f0(1370)f_0(1370) interfering with a smaller f0(1500)f_0(1500) component. There is evidence that the f0(1370)f_0(1370) signal is resonant, from interference with f2(1270)f_2(1270). There is also a state in ππ\pi \pi with M=1790−30+40M = 1790 ^{+40}_{-30} MeV/c2^2 and Γ=270−30+60\Gamma = 270 ^{+60}_{-30} MeV/c2^2; spin 0 is preferred over spin 2. This state, f0(1790)f_0(1790), is distinct from f0(1710)f_0(1710). The ϕKKˉ\phi K\bar K data contain a strong peak due to f2′(1525)f_2'(1525). A shoulder on its upper side may be fitted by interference between f0(1500)f_0(1500) and f0(1710)f_0(1710).Comment: 17 pages, 6 figures, 1 table. Submitted to Phys. Lett.

    Measurement of the Branching Fraction of J/psi --> pi+ pi- pi0

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    Using 58 million J/psi and 14 million psi' decays obtained by the BESII experiment, the branching fraction of J/psi --> pi+ pi- pi0 is determined. The result is (2.10+/-0.12)X10^{-2}, which is significantly higher than previous measurements.Comment: 9 pages, 8 figures, RevTex

    Search for K_S K_L in psi'' decays

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    K_S K_L from psi'' decays is searched for using the psi'' data collected by BESII at BEPC, the upper limit of the branching fraction is determined to be B(psi''--> K_S K_L) < 2.1\times 10^{-4} at 90% C. L. The measurement is compared with the prediction of the S- and D-wave mixing model of the charmonia, based on the measurements of the branching fractions of J/psi-->K_S K_L and psi'-->K_S K_L.Comment: 5 pages, 1 figur

    First observation of psi(2S)-->K_S K_L

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    The decay psi(2S)-->K_S K_L is observed for the first time using psi(2S) data collected with the Beijing Spectrometer (BESII) at the Beijing Electron Positron Collider (BEPC); the branching ratio is determined to be B(psi(2S)-->K_S K_L) = (5.24\pm 0.47 \pm 0.48)\times 10^{-5}. Compared with J/psi-->K_S K_L, the psi(2S) branching ratio is enhanced relative to the prediction of the perturbative QCD ``12%'' rule. The result, together with the branching ratios of psi(2S) decays to other pseudoscalar meson pairs (\pi^+\pi^- and K^+K^-), is used to investigate the relative phase between the three-gluon and the one-photon annihilation amplitudes of psi(2S) decays.Comment: 5 pages, 4 figures, 2 tables, submitted to Phys. Rev. Let

    First Measurements of eta_c Decaying into K^+K^-2(pi^+pi^-) and 3(pi^+pi^-)

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    The decays of eta_c to K^+K^-2(pi^+pi^-) and 3(pi^+pi^-) are observed for the first time using a sample of 5.8X10^7 J/\psi events collected by the BESII detector. The product branching fractions are determined to be B(J/\psi-->gamma eta_c)*B(eta_c-->K^+K^-pi^+pi^-pi^+pi^-)=(1.21+-0.32+- 0.23)X10^{-4},B(J/ψ−−>gammaetac)∗B(etac−−>K∗0Kˉ∗0pi+pi−)=(1.29+−0.43+−0.32)X10−4,B(J/\psi-->gamma eta_c)*B(eta_c-->K^{*0}\bar{K}^{*0}pi^+pi^-)= (1.29+-0.43+-0.32)X10^{-4}, and (J/\psi-->gamma eta_c)* B(eta_c-->pi^+pi^-pi^+pi^-pi^+pi^-)= (2.59+-0.32+-0.48)X10^{-4}. The upper limit for eta_c-->phi pi^+pi^-pi^+pi^- is also obtained as B(J/\psi-->gamma eta_c)*B(eta_c--> phi pi^+pi^-pi^+pi^-)< 6.03 X10^{-5} at the 90% confidence level.Comment: 11 pages, 4 figure

    Study of psi(2S) decays to X J/psi

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    Using J/psi -> mu^+ mu^- decays from a sample of approximately 4 million psi(2S) events collected with the BESI detector, the branching fractions of psi(2S) -> eta J/psi, pi^0 pi^0 J/psi, and anything J/psi normalized to that of psi(2S) -> pi^+ pi^- J/psi are measured. The results are B(psi(2S) -> eta J/psi)/B(psi(2S) -> pi^+ pi^- J/psi) = 0.098 \pm 0.005 \pm 0.010, B(psi(2S) -> pi^0 pi^0 J/psi)/B(psi(2S) -> pi^+ pi^- J/psi) = 0.570 \pm 0.009 \pm 0.026, and B(psi(2S) -> anything J/psi)/B(psi(2S) -> pi^+ pi^- J/psi) = 1.867 \pm 0.026 \pm 0.055.Comment: 13 pages, 8 figure

    Measurement of the Negative Muon Anomalous Magnetic Moment to 0.7 ppm

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    The anomalous magnetic moment of the negative muon has been measured to a precision of 0.7 parts per million (ppm) at the Brookhaven Alternating Gradient Synchrotron. This result is based on data collected in 2001, and is over an order of magnitude more precise than the previous measurement of the negative muon. The result a_mu= 11 659 214(8)(3) \times 10^{-10} (0.7 ppm), where the first uncertainty is statistical and the second is sytematic, is consistend with previous measurements of the anomaly for the positive and negative muon. The average for the muon anomaly a_{mu}(exp) = 11 659 208(6) \times 10^{-10} (0.5ppm).Comment: 4 pages, 4 figures, submitted to Physical Review Letters, revised to reflect referee comments. Text further revised to reflect additional referee comments and a corrected Fig. 3 replaces the older versio
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